Drug utilisation by children and adolescents with mental retardation: A population study

Objective: Little is known about the utilisation of drugs by mentally retarded children; population studies are even more sparse. In this study the chronic drug utilisation in children aged 4-18 years with mental retardation in a large population in the Netherlands was investigated.

Methods: Throughout all special schools and (day) care facilities for children with mental retardation in Friesland, parents/representatives were approached requesting participation of their children. Participants were interviewed about a number of aspects including medication use. For 921 of the 1,057 participants, information was available on medication use for those physical and psychiatric illnesses that bothered them or was expected to bother them for at least 3 months per year; 912 of the participants were within the age category under study: 4-18 years.

Results: About 22% of the 912 participants used chronic medication, 47% of whom used two or more drugs. The prevalence of drug use increased with severity of mental retardation from about 17% to 49%. The exception was the 6% of children with borderline intellectual functioning: their medication prevalence was 27%. Overall, 17% of the study population used a nervous system drug, 4% used a respiratory system drug and 3% used an alimentary tract drug. Of the drugs for the nervous system, alimentary tract and respiratory tract, 32% was prescribed off-label. For 3%, we were unable to establish on/off-label use.

Conclusions: Chronic drug utilisation patterns in children and adolescents with mental retardation are different from those in the general paediatric population. These different patterns suggest the need for additional research.